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An integrated Micropalaeontological analysis approach was employed based on ditch cuttings samples northwest of the Niger Delta. Lithofacies description showed the entire sediment successions consisted of alternating shale and sand lithology. A moderate to the rich recovery of about seventy-one foraminifera and forty calcareous nannofossil species were recovered, having the presence of Miocene foraminifera (Orbulina universa, Globigerinoides bulloideus, Globorotalia obesa, Globorotalia mayeri and Globorotalia continuosa) and nannofossil (Sphenolithus moriformis, Catinaster coalithus, Discoaster berggrenii and Discoaster kugleri). Three foraminifera planktonic zones were proposed for this study and were correlated to other worldwide zones; Globerigenoides bulloideus, Globeriginoides obliquus obliquus and Globerigenoides primordius spanning the Neogene (N) 6 to N17 zone. Two calcareous nannoplankton zones were proposed, which are; Helicosphaera intermedia and Sphenolithus moriformis spanning the Neogene Nannofossil (NN) 3 to NN11 zone. Three third-order sea-level rises and falls occurred during the Early to Late Miocene within the Niger Delta, with a corresponding paleo-waterdepth from transitional to outer neritic. The Chiloguembelina-3 Shale (16.0 Ma), Dodo Shale (11.6 Ma) and the Uvigerina-8 Shale (9.2 Ma), were associated with transgression. The 15.5 Ma SB of Depositional Sequence 1(Early Miocene), 10.5 Ma SB of Depositional Sequence 2(Middle Miocene) and 8.5 Ma SB of Depositional Sequence 3(Late Miocene) due to progradation. The paleosalintiy based on shell type morphology assemblages suggests a transition from the brackish marginal marine environment to open neritic conditions. The study interval is said to have penetrated sediments of the parallic Early to Late Miocene Agbada formation.